1. Field of the Invention
This invention relates generally to direct current (DC) magnet motors and, more particularly, to a magnetic motor system utilizing a plurality of ferromagnetic bodies (e.g. steel) on a stator which magnetically interact with a larger plurality of electromagnets on a rotor to turn a shaft, the electromagnets being energized in a predetermined sequence by commutator means on the stator.
2. Description of the Prior Art
It is well known that two magnetic poles of opposite polarity will attract each other. Furthermore, subject to certain restrictions, two magnetic poles of similar polarity will repel each other with a force which is directly proportional to the product of the individual pole strengths, and inversely proportional to the square of the distance separating them. The force is affected by the permeability of the medium through which the force acts which, for ordinary air, is nearly unity.
It is also well known that if any electric current is passed through a coil which is wrapped around a ferromagnetic core, the core will exhibit magnet properties in accordance with the direction of current flow. That is, the magnetic poles of the core may be reversed by reversing the direction of current flow in the coil
Permanent magnets and electromagnets are employed in motors and their forces of attraction and repulsion utilized to impose a force upon the motor's armature to cause rotation or to cause the armature to be linearly displaced. In the case of a rotating armature, a problem must be overcome which may be simply described as follows. Assume that first and second bar magnets, each having a north pole and a south pole, are mounted for rotation adjacent each other. The bar magnets will align themselves parallel to each other due to the substantially equal forces of repulsion between like poles. If the force of repulsion between a first pair of like poles were converted to a force of attraction, as by insertion of a ferromagnetic material therebetween, the first pair of poles would rotate towards each other while the remaining pair of like poles would rotate away from each other. Thus, the forces of attraction and repulsion have been utilized to create rotation. Unfortunately, when the first pair of poles (which now may be considered opposite poles since they are attracted to each other) arrive at a position most proximate each other, the system will lock up and, unless additional steps are taken, further rotation is impossible.
The same problem exists in the case of an electromagnet rotating past a ferromagnetic body (such as steel) or a permanent magnet of a polarity which attracts the electromagnet. When the electromagnet reaches a position most proximate the ferromagnetic body or the permanent magnet, the forces of attraction will be the strongest and will resist further rotation.
Referring again to motors employing permanent magnets and electromagnets, it has been necessary to provide additional magnetic interaction at the lock-up points to achieve continuous and uninterrupted rotation. In some cases, this is accomplished using elaborate and complex switching means to control the energization of the electromagnets and the orientation of the magnetic fields to produce the continuous motive power.